In hydrocarbon exploration and production operations, whipstocks are commonly used to guide a drill for milling a window in a well bore casing or slant-drill through the side of a well bore. Whipstocks are also often useful to guide a conductor shoe or pipe, working string, drill or other item for forming a new well bore adjacent to an existing well. As used herein, the term “tubular member” means an item that can be guided by a whipstock, such as, depending upon the application, a conductor shoe or pipe, working string, drill, drill bit or a combination thereof. In many situations, such as in offshore drilling operations, a common challenge is to prevent hang-up of the tubular member on structural components located at the existing well location.
Various presently known whipstock technologies are believed to have one or more limitations. For example, when forming new well bores adjacent to existing wells, various known whipstocks are believed to be capable of only directing the tubular member over the outer diameter of the existing well stump and not over adjacent structural components that may be present at the site. Consequently, when an obstruction is encountered during whipstock operations at offshore sites, it is often necessary to send divers to the sea floor to pull the pipe across the obstruction(s) or abandon the effort completely. For another example, some presently known whipstocks allow the tubular member to roll off the whipstock center, decreasing the accuracy of azimuth target achievement.
It should be understood that the above-described examples, features and potential limitations are provided for illustrative purposes only and are not intended to limit the scope or subject matter of this disclosure or any related patent application or patent. Thus, none of the appended claims or claims of any related patent application or patent should be limited by the above examples, features and potential limitations or required to address, include or exclude the above-cited examples, features and/or potential limitations merely because of their mention above.
Accordingly, there exists a need for improved whipstocks and related systems and methods for guiding a tubular member having one or more of the attributes, capabilities or features listed below or as may be described in or evident from the subsequent sections of this disclosure, appended claims and drawings: utilizes a self-actuated deflector to force the tubular member a sufficient distance from the whipstock or existing well bore; utilizes a deflector that is actuated upon landing the whipstock in an existing well bore stump; utilizes a deflector actuator that includes a setting ring and biasing member; utilizes a hydraulically or pneumatically actuated deflector to force the tubular member a sufficient distance from the whipstock or existing well bore; utilizes a deflector delivered in a retracted position to allow the whipstock to pass through one or more pipe guides and movable into a deployed position to guide the tubular member as desired; assists in eliminating the need for prolonged diver operations to ensure proper clearance of a tubular member around existing structural components at offshore locations; assists in preventing hang-up of the tubular member on structural components at the well site, such as conductor guide frames, funnels or other mud-line jacket components; prevents roll-off of the tubular member from the whipstock; may assist in forcing the tubular member away from the existing well bore center up to approximately 150% of the existing stump diameter; may be useful at or below mud-line at offshore drilling sites or at or below surface at land-based drilling sites.